Originally Posted By: paul

maybe we should use dyne as our force because we are not affected by earths gravity in space , in fact lets move the

The SI definition of the newton is exactly what you want -
"the force required to accelerate a mass of one kilogram at a rate of one meter per second squared".


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the reason I reason the above is because at impact the
product of the impacting objects mass x its velocity is the force that another object will feel. so it does not matter

How many times do I have to tell you that acceleration is not the same a velocity? The product of a mass and a velocity is not a force! To experience a net force it must accelerate, and it must accelerate at the same time as the force is being applied, not immediately beforehand.

What this means is the force depends on how quickly the object slows down when it hits something. That's the acceleration you can use to determine the force by F=ma. But it's also difficult to calculate, and it varies with time - as I've mentioned before.




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what the impacting objects rate of acceleration was before the impact.

Not relevant to the force of the impact.


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a object with a mass of 1 kg and a velocity of 10 m/s strikes a wall with a force of 1 kdf

Most of the time that will be wrong. If you put a force meter on the wall, you'll find the force is usually not 1kdf. Did you completely ignore my last message? The force of the impact depends on the deformation of the objects - ie the materials they're made from.

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this way I can use the word force while trying to discuss what were trying to discuss.

What you call "force" above is effectively "impulse" (apart from the wrong units). If you want to use it, call it impulse because it's not a force. And use the correct units. Multiplying kg by m/s always gives kg.m/s, which is a unit of impulse.


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the product of the masses mass x its velocity = mv

That's it's momentum. If you're talking about the collision, and v is the relative velocity immediately before, and the object stops, then it's the impulse. I'm pretty sure you mean impulse.


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a = the product of the masses mass x its velocity / Mass

That's a velocity, not an acceleration. Calling it "a" will be endlessly confusing. Call it v or v_mass or whatever distinguishes it from other velocities.